Technological devices are used to measure both speed and breath alcohol concentration. In court, the results of those devices are introduced to prove defendants are guilty of speeding or DUI (called ‘OVI’ in Ohio). As the government has the burden of proving a defendant’s guilt, one would expect the government would have the obligation to prove the measurement device produced an accurate result. A recent decision of the Ohio Supreme Court permits judges and juries to presume the measurement devices are accurate.